1. Field of the Invention
This subject invention relates to thermostatic water valves for use in internal combustion engine cooling systems and particularly to a thermostat housing assembly for mounting on an engine to control coolant flow.
2. Description of the Prior Art
During operation of a cold engine it is desirable to prevent cooling water from flowing through the radiator in order to reduce the time required for the engine to reach an optimal running temperature, which is achieved by diverting cooling water from the discharge side of the water pump back to the engine block through a bypass conduit and blocking its return path to the radiator.
A conventional thermostat for an engine includes a valve biased to a closed position by a spring and includes an expandable system that expands in response to heat to open the valve against the spring. The thermostat includes a metal carrier that is disposed in the housing before the housing is mounted into sealed relationship with the engine. The thermostat is often placed in the housing before the housing is mounted on the engine.
Various prior art designs of thermostat assemblies are taught by U.S. Pat. No. 4,196,847 to Gobien; U.S. Pat. No. 4,280,655 to Duprez et al.; U.S. Pat. No. 4,456,167 to Buter; U.S. Pat. No. 5,163,613 to Ragan, and U.S. Pat. No. 5,669,363 to Francis and are widely used in an automotive industry. It is often a problem to obtain adequate sealing and to retain the thermostat valve and/or the seals in position during shipment and handling of the assembly before mounting on the support structure of an engine.